CP Violation in Heavy Neutrino Mediated e−e−→W−W−e^- e^- \to W^- W^-

We consider the reaction $e^- e^- \rightarrow W^- W^-$ mediated by possible heavy neutrino exchange at future LINAC energies of $\sqrt{s}>> 2 m_W$. This reaction is sensitive to CP phases of the neutrino mixing matrices, even at the level of Born amplitudes. Certain integrated cross-sections are shown to have the power to resolve the CP phases when the experimental configurations are varied. Asymmetries sensitive to CP violation (involving initial QED phases) for $e^- e^-$ and $e^+ e^+$ reactions are constructed and their consequences considered.Comment: 9 pages plain Latex and 4 figures available separately as uuencoded figure

Physics with Like-Sign Muon Beams

We point out that both the specific lepton number content and the high energies potentially attainable with muon-muon colliders make it advisable to consider the technical feasibility of including an option of like-sign incoming beams in the studies towards a proposal to build a muon-muon collider with center-of-mass energies in the TeV region. This capability will add some unique physics capabilities to the project. Special attention will have to be paid to polarization retention for the muons.Comment: 13 pages, uuencoded postscript file, also available from ftp://gluon.hep.physik.uni-muenchen.de/preprints/scipp9534.u

A Reproducible Study on Remote Heart Rate Measurement

This paper studies the problem of reproducible research in remote photoplethysmography (rPPG). Most of the work published in this domain is assessed on privately-owned databases, making it difficult to evaluate proposed algorithms in a standard and principled manner. As a consequence, we present a new, publicly available database containing a relatively large number of subjects recorded under two different lighting conditions. Also, three state-of-the-art rPPG algorithms from the literature were selected, implemented and released as open source free software. After a thorough, unbiased experimental evaluation in various settings, it is shown that none of the selected algorithms is precise enough to be used in a real-world scenario

Model-Independent Z′Z' Limits from Electron-Electron Collisions

Model independent constraints on the mass of an extra neutral gauge boson and its couplings to charged leptons are given for the $e^-e^-$ option of a future linear collider. Analytic exclusion limits are derived in the Born approximation. The results are compared with those of the $e^+e^-$ mode. The influence of radiative corrections is discussed.Comment: 7 pages, LaTeX, 4 Figures, uuencoded Postscriptfile, MPI-Ph/94-23, LMU-04/9

El cuento de senderos que se bifurcan. El Noble cuento del enperador Carlos Maynes y sus encrucijadas genéricas

Tras un breve balance del estado de la cuestión en cuanto a las fuentes del Carlos Maynes, este trabajo estudia los cambios genéricos que obran en este relato: paso de «cantar de gesta» a «cuento maravilloso», es decir a relato en prosa de aventuras caballerescas; del docere al delectare; del tema de las reinas injustamente acusadas a la problemática del buen gobierno en el espacio conflictivo de la corte. Estos cruces temáticos nuevos del Carlos Maynes abren, además, muchas puertas: nuevos grupos sociales pueden entrar a formar parte del espacio literario –con la creación de personajes como los villanos Barroquer y Griomoart–, pero también nuevos tonos y estilos como por ejemplo la mezcla de burlas y veras. Se insiste también en la posición del relato en la antología escurialense. El hecho de que sea el relato con el que se cierra el códice es altamente significativo si pensamos que la obra es totalmente inaugural: es la magistral obertura, con todos sus leitmotivs, para anunciar los futuros libros de caballerías como el Zifar y el Amadís

On Possibility of Detecting the E-E- -> W-W- Process in the Standard Model

We examine the e-e- -> W-W- lepton number violating process in the frame of the Standard Model with additional right-handed neutrino singlets. We give results in the framework of the `see-saw' as well as other models, where there is no relation between neutrino masses and the mixing matrix elements. The cross section for the `see-saw' models is negligible because they predict in a natural way very small electron-heavy neutrino mixing angles. However, there exist other models, in which the electron-heavy neutrino mixing angles are free parameters and can be large. Taking into account the present experimental bounds on mixing angles the large cross section for the e-e- -> W-W- is still acceptable.Comment: 16 pages, LATEX file and 4 tar-compressed uuencoded figure